Photographic camera shutter



A. P. svl-:NssoN 2,512,815

PHOTOGRAPHIC CAMERA SHUTTER June 27, 1950 Filed March 15, 1949 PatentedJune 27, 1950 UNITED 'STATES PATENT OFFICE PHOTOGRAPHIC CAMERA SHUTTERAlgot PercyrfSvensson, Goteborg, Sweden Application March 15, 1949,Serial No. 81,489- In Sweden November 7,' 1946 4 Claims. 1

This invention relates to photographicy shutters of the kind including apair of curtains Wound on spring-actuated rollers. One object of myinvention is to provide a shutter mechanism having a single,manually-operable knob for rewinding the shutter to condition itfor anexposure and for adjusting the shutter to obtain the required time ofexposure. Another object of my invention is to provide a shuttermechanism in which the manually operable knob,when used for setting theshutter to obtain therequired time of exposure, is not subjected to theinfluence of the springsfacting on the curtains. Another object of myinvention is to provide a shutter `which may be set to fgive the desiredexposure time before, after or during the winding operation. Stillanother object of my invention is to provide a shutter which isnoiseless` during the actual exposure even when it is set for acomparatively long exposure time, say `between 1A, and 1 second.

In order that the principle of the invention may be readily understood,I have disclosed one embodiment thereof in the accompanying drawings,wherein- Figure l is a diagrammatic perspective view of the shutteractuating and setting-mechanism; Figure 2 shows diagrammatically and in/section the curtains and the curtain'roller shafts;

Figure 3 is a, perspective view of a part of Figure 2;

Figure 4 is a plan view of a part of Figure 2, and

Figure 5 is a perspective view of the setting mechanism in a positiondifferent from that shown in Figure 1.

In the drawinlgs, I denotes the curtain which is the first to beactuated 'when the shutter mechanism is released for an exposure(hereinafter called the rst curtain), said curtain thereby being woundup on a spring-actuated roller 2 in conventional manner as a pair ofribbons 3 attached to the trailing edge of the curtain unwind from arotatably mounted shaft 4 (see Figure 2). A curtain 5 (hereinaftercalled the second curtain) follows the .first curtain and, prior tomaking the exposure, is wound on a shaft 6 extending parallel to theshaft 4, a pair of ribbons 'I attached to itsleading edge being wound ona spring-actuatedV roller 8 in making an exposure. At the beginning ofan exposure, the shaft 4 is released to wind the iirst curtain on theroller 2 under the influence of the spring acting thereon. As thetrailing edge of the first curtain is drawn across the exposure frame 9of the camera, the shaft 6 is released after a predetermined timeinterval so that-the ribbons 1 are wound on the spring-actuated roller 8and pull the second curtain 5 to a position in which it covers theexposure frame -9. The mechanism may also be set so that after therirstcurtain hasfmoved a predetermined distance the yshaft 6 is :released tofree the second curtain. In :this case, a slot 9d which is formedbetween the trailing edge of the first curtain and the leading edge ofthe second curtain passes in front of the exposure frame and effects theexposure.

On the shaft 4 there is attached a toothed wheel Ill in mesh with arotatably mounted toothed wheel Il, and on the shaft 6 there is attacheda'toothed wheel I2 Lin mesh with a rotatably mounted toothed wheel I3rwhich is mounted coaxially with the toothed wheel Il. A manuallyrotatableknob I4' is disposed exteriorly'of the'camera casingLandarotatably mounted circular disc I5 is arranged coaxially with, andadjacent the inner face of the knob I4,l the disc I5'being free torotate only in the direction indicated by the arrow Ain Figure 1.Theidisc I5'is provided with a series of `holes or openingsl'distributed along itsperiphery for selective engagement by an axiallyprojecting'A pin I'I `on the knob I4-as shown in Figure 1. A shaft l'towhich the knob I4 is rigidly attached is axially slidable; and the knobI4 may be pulled outwardly against the action of a spring :coil I9 so asto bring the pin Il out of engagement'with the hole I5. By rotating theknobV I4 rwhen it occupies the withdrawn position, the pin Il may bebrought in position in front of any selected one of the holes I6 yandwill engage ytherein upon releasing the knob. A toothed `wheel 2l xed toa hub extension 20 of the disc I5 meshes with a pinion 22 rigidlyconnected to a rotatably mounted shaft 22a to which there is attached abevel gear wheel 23 meshing with a bevel gear ypinion 24 attached to acoupling sleeve 25 which isv mounted on the shaft 4 and is angularly,but not axially, displaceable relative thereto. On the shaft 4 there isslidably mounted another coupling sleeve 25 which is prevented fromrotating relative to the shaft `by conventional means. As the couplingsleeve 26 engages the coupling sleeve 25,' the rotation of the latter istransmitted to the shaft 4. By rotating the knob I4 in the direction ofthe arrow A, when the pin I'I engages one of the holes I6 of the discI5, a rotational movement is imparted to the shaft'4 in the direction ofthe arrow B, whereby the ribbons 3 'of they curtain I are wound up onthe shaft 4` 'and the curtain I is brought to the set position shown inFigure 2 in front of the exposure frame 9.' The rotation of the shaft 4is transmitted by means. of the toothed wheel I0 to `the toothedwheel IIlwhich is rotated in the direction of the arrow C. A lip 2l provided onthe toothed wheel I I contacts a pin 28 projecting from the toothedwheel I3 and transmits this rotation to the toothed wheel I3, therotational movement of this wheel being transmitted by means of thetoothed wheel I2 to the shaft 6 which is caused'to rotate inthedirection of the arrowD, whereby the curtain. 5 is woundlon. the shaft 6andvis drawn across the exposure frame vtacts the surface 35a of theabutment 35. vmeans of mechanisms which will be hereinafter 9 to theposition shown in Figure 2. This rotation is stopped when the pin 28lcontacts a xed abutment 30 and, as the knob I4 is released, the movablemembers hereinbesfore described are retained in their position owing tothe fact that the dise I can be rotated only inthe direction of thearrow A.

An arm 34 actuated by a coil spring 35 projects from a disc 32 attachedto a rotatable shaft 3| 1 and may be retained in the position shown inFigure 1 against the action of said spring by means of a pivotallymounted latch 35. By means of a shutter release lever (not shown), thelatch 35 may be swung to a position in which it releases the arm 34.When released, the arm 34 will swing to a position under the influenceof the spring 33 in which it pivots to an inoperative position a pawl36, which normally maintains the coupling sleeve 26 in engagement withthe coupling sleeve 25, so that the coupling sleeve 26 is disengagedfrom the coupling sleeve 25 by means of a spring 31, thus disconnectingthe shaft -4 from the disc I5. The roller 2 is now free to -Wind up thecurtain I which, in turn, rotates the shaft 4, this winding of thecurtain I being stopped as the lip 21 of the toothed wheel IIparticipating in the movement of the shaft 4 condescribed, the toothedwheel I3, which is connected to the shaft 6 of the second curtain 5 bymeans of the toothed wheel I2, is locked during the initial movement ofthe first curtain I but is released automatically when the toothed wheelIl has rotated through a predetermined angle, so that the roller 8- isfree to wind up the second curtain 5 after the formation of the slot 9between the trailing edge of the rst curtain I and the leading edge ofthe second curtain. The toothed wheel I3 may also be locked until acertain interval of time has elapsed after winding up the first curtainso that the exposure frame is entirely uncovered for a predeterminedlength of time.

At the side of the toothed wheel I 3 remote from lthe toothed wheel IIthere is rotatably mounted a toothed wheel 40 arranged coaxially withthe first mentioned toothed wheels and having connected rigidly theretoa substantially circular `disc 4I situated between the toothed wheels Iland I3. Ihe toothed wheel 40 meshes with a pinion 42 rigidly attached toone end of a rotatably mounted shaft 43, to the other end of which thereis attached a bevel gear 44 meshing with another bevel gear 46 attachedto a rotatably mounted shaft 45. To said shaft 45 there is attached acylindrical toothed wheel 41 perma- VKnently meshing with a toothedwheel 48 attached to the shaft .I9 of the knob I4, so that by rotatingthe knob I4 the toothed wheel 4i? and the disc 4I are rotated in theappropriate direction. A pawl 50, in the form of a double-armed leveractuated by a spring 4B, is pivotally mounted on the disc 4I and isadapted to co-operate with a series of axially projecting pins 5Idistributed around the toothed wheel I3. Normally the pawl 5U isrestrained from engagement with said pins 5I by means of a ring 53axially adjustable along the hub 52 of the toothed wheel II and engaginga pin 54 projecting from the pawl 50 and passing through a recess in thedisc 4I, the pin 54 being held against the peripheral edge of said ring53 by means of the spring 49. The ring 53 is connected by means of twothin rods 555 passing through apertures in the toothed Wheel II to ayoke 56, which is rotatably carried by ,wardly (as viewed in Figure l)against the action of the spring 5l as the disc 32 performs itsaforesaid angular movement from the position shown in Figure l to theposition shown in Figure 3. By means of this upward movement of theslide 58, the ring 53 is pulled towards the toothed wheel II and awayfrom the pin 54 so that the latch 58 under the action of the spring 49is free to swing to the position shown in Figure 15in which it engagesthe pin 5I disposed in front thereof and prevents the angulardisplacement of the toothed wheel I3. In this position of the latch 55,the ring 53 is restrained by the pin 54, against the free end of whichthe ring 53 is urged by the spring 5i' as the slide 58, at the end ofthe aforesaid angular movement of the disc 32, is released by the lip5S.

A pin 65 is attached to the toothed wheel II and is directed towards thering 53 which, at its edge, is provided with a recess for the receptionof said pin. As the toothed wheel II rotates in the direction of thearrow E the pin 65 contacts the pin 54 carried by the latch 55 andswings the latch back to the inoperative position. In this position ofthe latch 5G the ring 53 is no longer supported by the pin 54 and thering 53 returns to the lowered position under the infiuence of thespring 5l. Thus, upon release of the latch 56, the toothed wheel I3 isfree to rotate and the roller 3 can wind up the second curtain 5 fromthe shaft 6. The width of the slot 9 between the first curtain I and thesecond curtain 5 is dpendent on the position in which the disc 4lcarrying the latch 50 has been setin relation to the toothed wheels IIand I3. The angular distances between the pins 5I of the toothed wheelI3 `correspond to the angular distances between the holes I5 of the discI5 and, by pulling out the knob I4 so as to disengage the pin Il fromthe disc I5 and turning the knob in the` appropriate direction, it ispossible to set the disc 4I carrying the latch 56 in any desired angularposition and, consequently to pre-set the size of the slot 9 formedbetween the curtains I and 5 when releasing the shutter mechanism for anexposure. It is to be observed that this setting can be performedbefore, during or after bringing the curtains to the position shown inFigures l and 2, i. e. the position ready for exposure.

When rotating the disc I5 by means of the knob I4 in order to bring theshutter parts to the position shown in Figure 2, a pin 35 projectingfrom the disc I5 contacts an arm 8l projecting from a rotatably mountedshaft `B6 and rotates said shaft through a certain angle. Another arm 83projecting from the shaft 86 actuates a slide 89 against the action ofthe spring 31 to move the coupling sleeve 26 into engagement with thecoupling sleeve 25, the two sleeves being locked together by means ofthe latch 36. To the disc I5 there is attached another projecting pin 95which, upon further angular movement of the knob I4, contacts an arm SIprojecting from the shaft 3| and swings the disc 32 and the arm 34 fromthe position shown in Figure 3 to the position shown in Figure l,whereby the latch 35 (adapted to be actuated by the shutter releaselever) retains the arm 34v in the last mentioned position. The knob isprovided in known manner with a dial indicating the exposure timecorresponding of the disc 4 I'is shown in Figure 5. The exposure timesobtained' by such angular positions of the disc 4I may be varied between1/1600 and 1/5 second.

lWhen a somewhat longer `exposure time is desired, for instance 1 to T16second, the disc 4I is set'by means ofthe knob I4-in, or in the vicinityof, the angular position shown in Figure l.

lthis position of the disc v4 I the latch 53 is brought out of'engagement with the pin 5i bymeans of 'a two-armed lever 65a pivotallymounted on the disc 4I. One arm `iI of the lever Ella. is kept incontact with the pin 54 of the latch 5l! by means of a spring 62 and, insaid position of the lever 60a, Ythe'other lever' arm 53 is directedsubstantially vradially'fr'om the centre of revolution of the disc 4I."At a distance from thedisc 4l there is' pivotally mounted on a shaft 64a toothed segment 66 having an actuating spring 65 and an karm 68projectingtowards the disc 4I and pro- :vided kat its' free end with apin 61. toothed wheel Il there is attached 'apin 68a di- To the rectedtowards the toothed wheel I3 and adapted toturn the arm 58 against theaction of the *spring 651 whenl thetoothed wheel II as aforesaidisrotated inA thel direction of' the arrow C. In

vthis position of the arm'l68, the pin 61 is disposed at a distance fromthe leverarm 63, said distance being dependent on the angular positioninwhich the disc 4I'has been set. The toothed segment 66 meshes with arotatablymounted pinion 10 which is coupled byY means of auni-directional `coupling 1Iv to a-toothed wheel 12 meshing with `apinion 13 attached to a worm wheel 14.

` worm wheel 14 drives a worm 15 to which an air "propeller 16L is'attached.

This

When l'releasing the shuttermechanisrn by actuatingthe latch-35 by meansof the shutter release lever (not shown), the arm 34 is released and,under the action of the spring'33, is moved 'angularly to a position inwhich the latch 36 is *caused to release the coupling sleeve 25, where-"upon theroller 2 is free to wind up Vthe first curtainA I from theexposure'frame 9. the shaft 4 rotates the toothed wheel II in theRotation of direction of the arrow Eso that the pin 68a releases thelarm 68 which; under the iniluence of the spring 65, commences to movetowards the lever arm 63, being retarded by the air propeller 16. Whenthe pin 61 contacts the lever arm 53, the leverl 60a is pivoted so as tobring the latch 50 out of engagement with the pin 5I on the toothedwheel I3, thus allowing the roller 8 to wind the ribbons 1 of the secondcurtain 5 to a position in front of the exposure frame 9. As the latch50 is disengaged from the pin 5I, the ring 53 is free to enter betweenthe pin 54 and the hub 52 so that the latch 50 is retained in aninoperative position when, at the completion of an exposure, the shutteris again brought to a position ready for the next exposure, the pin 68aon the toothed wheel II again swinging the arm 68 to the position shownin Figure 1.

It will be evident without further explanation that the interval of timebetween winding Y the rst curtain-land the release of the second fv`c`i1rtaini5 fis-dependent on' the angle through..VA

' vwhich the arm` 68 after having been released by the pin 68a, hasto'passv through before its pin 31 contacts the arm `63, saidanglebeing'dependent on the angular position vin which the disc 4I isYset-by means of the'knob I4 relative-to the toothed-wheels' I-I and I3.The angular distances between the holes I6 ofthe disc I5 correspond tothelangular distances between the pins 50 and the dial of the knob I4indicates the vexposing time corresponding'to the selected angularposition of the disc 4I.

From vthe above description4 it will be obvious that for short exposureAtimes, for instance from YV1/25 to '1/1500 second, the disc 4I is setrelative to the toothed wheels II and I3 by means of -the knob I4 sothat the wheel II restraining the first curtain I must rotate, whenreleased, agreater or smaller angle before its pin B0 contacts thepin 54ofthe latch 5I) and by swinging the latch-50 to an inoperativeV positionreleases the toothed wheel" I3 restraining the second curtain 5 so Ithatthe "latter 5 isiree tofollow therstrcurtain I. For longerexposure-times, for-instance from-1 to le second, the' disc 4I is set insuch 'an angular position relative to the toothed` wheels- II- and I3vthat when the 'toothedewheel yII is releasedfor making an exposure itsangular movement is stopped by the -lip 21 as its front edge contactsthe surface`3a ofthe abutment 30 before the pinA 60 reaches the pin 54of the latch 5I; Furthermore, the angular position of the disc-4I issuch-that the lever arm G3 is disposed at a greateror smallerdistancefrom the pin 61' oftheV arm 68,-and a v4longer or shorter timewillpass, before the pin 61 rotation of said knob, when'occupying one ofits axial positions,v to the lockable'roller of the rst curtain forwinding upisaid curtain'on said roller against the tension of its springroller, means for transmitting said rotational movement of the lockableroller of the rst curtain to the lockable roller' of the 'second'curtain for winding up said second curtain on its lockable rolleragainst the action ofits spring roller, said movement transmitting meanscomprising two coaxial, rotatable toothed wheels meshing respectivelywith pinions attached to the lockable roller of the first curtain andthe lockable roller of the second curtain and between said toothedwheels a uni-directional coupling, a rotatable disc mounted coaxiallywith saidtoothed wheels, means for transmitting the rotation ofthe'knob, when occupying its other aXial position, to said disc forsetting said disc I toothed wheel reaches a predetermined angularposition.

2. A shutter mechanism for photographic cameras including a rstcurtainand aV second curtain, each curtain having a spring roller at one endand a,v lockable roller at the other-end for retaining the curtain in aYset position, a manually rotatable knob capable of being set in twodiierent axial positions, means for transmitting the rotation of saidknob, when occupying one of its axial positions, to the llockable rollerof the first curtain for winding up said curtain on said roller againstthe tension of its spring roller, means for transmitting said rotationofk the'lockable'roller ofthe iirst curtain to the lockableroll'er ofthe secondcurtain for winding up said second'curtain on its lockableroller against the action of its spring roller, said movementtransmitting means comprising two coaxial, rotatable toothed wheelsmeshing respectively with pinions `attached to the lockable roller ofthe rst curtain and the lockable roller of the second curtain andbetween said toothed lwheels a uni-directional coupling, a rotatabledisc mounted coaxially with -said toothed wheels, means for transmittingthe rotation of the knob, when occupying its other `axial position, tosaid disc for setting said dise in diierent angular. positions, a latchpivotally mounted on said disc and adapted to co-operate with a seriesof pinsdistributed along the edge of the toothed wheel meshing with thepinion attached to the lockable roller of the second curtain to locksaid toothed lwheel to said discinv ,dierent angular positions of thelatter, and a ually rotatable knob capable ofY being set intwo differentaxial positions, means for transmitting therotation of said knob, whenoccupying oneof its axial positions, to the" lockable roller of the 'rstcurtain for'winding up said curtain on said roller against the tensionof Vits spring roller, means for transmitting said rotationof'thelockable nroller of the rstcurtain to the lockable roller of the secondcurtain'for winding up said second curtain on its lockable rolleragainst the action of its spring roller, said movement transmittingmeans comprisingtwo coaxial, rotatable toothed wheels meshingrespectively .with pinions Y,

attachedto the lockable roller of the rst' curtain and thelockableroller of the second curtain and between said toothed wheels auni-directional coupling,` arotatable disc mounted coaxially with saidtoothed wheels, means for transmitting the rotation of the knob, whenoccupying its other axial position, to said disc for setting said' discin diiierent angular positions, a spring-actuated latch pivotallymounted onV said disc and adapted to `co-operate with a series of pinsdistributed along the edge of the toothed wheel" meshing with the pinionattached to the lockable roller of the second curtain, means fornormally holding said latch out of engagement with said Vpins and forreleasing said latch when the shutter mechanism is released for anexposure, so as to permit the latch to engage the pin in front thereofand to lock said toothed wheel to said disc in the pre-set angularposition of the latter, and a the pinion of the lockable roller of therst curtain and capable of unlocking said latch when the last mentionedtoothed wheel reaches a predetermined angular position.

4. A shutter mechanism for photographic cameras including a rst curtainand a second curtain, each curtain having a spring roller at one end anda lockable roller at the other end for retaining the curtain in a setposition, a manually rotatable knob capable of being set in twodierlVent axial positions, means for transmitting the rotation of saidknob, -when occupying one of its axial positions, to the lockable rollerof the iirst curtain'for winding up said -curtain on said roller againstthe tension of its spring roller, means for transmitting said rotationof the lockable roller of the rst curtain to the lockable roller of thesecond curtain for Winding up said second curtain on its lockable rolleragainst the action of its spring roller, said movement transmittingmeans comprising two coaxial, rotatable toothed wheels meshingrespectively with pinions attached to the lockable roller of the firstcurtain and the lockable roller of the second curtain and between saidtoothed wheels a uni-directional coupling, a rotatable disc mountedcoaxially with said toothed wheels, means for transmitting the rotationof the knob, when occupying its other axial position, to said disc forsetting said disc in different angular positions, a spring-actuatedlatch pivotally mounted on said disc and adapted to cooperate with aseries of pins distributed along the edge of the toothed wheel meshingwith the pinionatta-ched to the lockable roller of the second curtain,means for normally holding said latch out of engagement with said pinsand for releasing said latch When the shutter mechanism is released foran exposure, so as to permit the latch to engage the pin in :frontthereof and to lock said toothed wheel to said disc in the pre-setangular position of the latter, a double-armed leverV pivotally mountedon said disc and capable of movement to unlock said latch, aspring-actuated arm pivotally mounted in the proximity of the disc anddirected substantially towards the disc, a projection attached to thetoothed wheel meshing with the pinion of the lockable roller of thefirst curtain and capable of holding said arm against the action of itsspring as the shutter mechanism is set and of releasing said arm as theshutter mechanism is released for an exposure, one arm of said levernormally projecting substantially radially with respect to the centre ofrotation of the disc and disposed in the path of movement of saidspring-actuated arm at a distance therefrom dependent on the angular Yposition in which the disc is set, and an air pro- ALGO-T PERCY SVENSSO-N.

REFERENCES CTED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Name Date Berger Dec. 12, 1905 Number projectioniixed to the toothed wheel meshing with 2,257,012 f Hinelne- Sept. v2 3,1941,

